The researchers studied more than 18,000 men without Parkinson’s disease who had provided blood samples between 1993 and 1995 and whose subsequent health status was followed. The researchers found that men in the top quartile of blood urate concentration had a 55% lower risk of developing Parkinson’s disease than men in the bottom quartile.
This difference was not explained by differences in age or other risk factors for Parkinson’s disease. The results of two previous studies had suggested a possible inverse relation between blood urate and risk of Parkinson’s disease, but it was only when the previous data were combined with those of the new study that the evidence became compelling.
The authors hypothesize that urate’s antioxidant properties may help dampen the effects of oxidative stress, which appears to contribute to the progressive loss of the dopamine-producing brain cells that occurs in individuals with Parkinson’s disease. The author’s believe that if this is the case, elevating blood urate could be helpful for patients with the diesase.
To back-up this speculation, the researchers accessed the databases of two large, randomized studies conducted among patients with early Parkinson’s disease. The preliminary results showed a slower progression of the disease among individuals with high blood urate.
“It is still uncertain whether urate exerts a neuroprotective effect, but approaches to elevating urate levels are nonetheless worth considering as a potential neuroprotective strategy,” said Alberto Ascherio, associate professor of nutrition and epidemiology at Harvard School of Public Health and senior author of the study.
The researchers are now designing a clinical trial in individuals with Parkinson’s disease to examine urate’s neuroprotective effects. However, Mr Ascherio warned: “elevating blood urate increases the risk of kidney stones and may have adverse cardiovascular effects and should only be attempted in the context of a closely monitored randomized trial until beneficial effects are proven.”